JP6567027B2 - Absorbent articles - Google Patents

Description

  The present invention relates to an absorbent article such as a sanitary napkin.

  An absorbent article that absorbs a liquid material such as menstrual blood includes an absorbent body having a longitudinal direction for absorbing the liquid material. The absorbent body has an absorbent core and a core wrap sheet that covers the absorbent core. Some absorbent cores have grooves formed along the skin of the wearer wearing the absorbent article (see, for example, Patent Document 1).

JP, 2015-112235, A

  The sanitary napkin as an absorbent article is attached so that the rear part thereof corresponds to the wearer's buttocks. In particular, the sanitary napkin for nighttime has a long rear part in order to suppress liquid leakage at the rear part, and the rear part of the sanitary napkin is formed so as to substantially cover the buttocks. Since the heel portion has a shape in which the rupture portion is suddenly depressed with respect to the swelling of the heel portion, a gap is easily generated between the rupture and the sanitary napkin at the rear portion of the sanitary napkin. For this reason, liquid substances such as menstrual blood excreted from the excretion area of the wearer tend to flow to the rear part through a rupture, and liquid leakage may occur in the rear part.

  The subject of this invention is related with the absorbent article which can suppress the liquid leak in a rear part.

The absorbent article which concerns on one form of this invention comprises an absorptive core.
The said absorptive core has the front core part and back core part which are located in the both ends part side of a longitudinal direction.
The rear core portion is arranged in a width direction orthogonal to the longitudinal direction and is provided in a plurality of first groove portions extending in the longitudinal direction, and on the center side in the width direction with respect to the first groove portion. And a structural surface including one or a plurality of second groove portions wider than the plurality of first groove portions.

  As described above, according to the present invention, liquid leakage at the rear part of the absorbent article can be suppressed.

It is a perspective view showing an absorptive article of a 1st embodiment of the present invention. It is a top view of the absorptive article. It is sectional drawing cut | disconnected by the III-III line of FIG. It is a top view which shows the absorptive core of the said absorbent article. It is the schematic which shows the deformation | transformation state of the napkin at the time of wearing the said absorbent article. It is a top view of the absorptive core of the 2nd Embodiment of this invention. It is a top view of the absorptive core of the 3rd Embodiment of this invention. It is a top view of the absorptive core of the 4th Embodiment of this invention. It is a top view of the absorptive core of the 5th Embodiment of this invention. It is a top view of the absorptive core of the 6th Embodiment of this invention. It is a top view of the absorptive core of the 7th Embodiment of this invention. It is sectional drawing of the intermediate | middle core part of the absorbent article in which the absorptive core of 7th Embodiment was integrated. It is a top view of the absorptive core of the 8th Embodiment of this invention. It is a fragmentary top view which shows the modification of the absorptive core of 1st Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the drawing, an X axis, a Y axis, and a Z axis are shown.

<First Embodiment>
[Overall structure of napkin]
FIG. 1 is a perspective view showing an absorbent article 1 according to an embodiment of the present invention. In FIG. 1, the X-axis direction corresponds to the front-rear direction, the Y-axis direction corresponds to the left-right direction, and the Z-axis direction corresponds to the up-down direction.
FIG. 2 is a plan view of the absorbent article 1 and shows an aspect in which the absorbent article 1 shown in FIG. 1 is extended along the XY plane. In the absorbent article 1 shown in FIG. 2, the X-axis direction corresponds to the longitudinal direction, the Y-axis direction corresponds to the width direction, and the Z-axis direction corresponds to the thickness direction. Hereinafter, unless otherwise specified, the longitudinal direction, the width direction, and the thickness direction mean each direction in the absorbent article. Hereinafter, the absorbent article 1 is demonstrated in the aspect shown in FIG.
The absorbent article 1 of this embodiment is configured as a sanitary napkin, and is hereinafter referred to as a napkin 1.
The napkin 1 of the present embodiment is used at the time of daytime activity or at bedtime, and if used at bedtime, for example, the length of 30 cm or more along the X-axis direction that is the longitudinal direction is used. You may have.

  In this embodiment, the napkin 1 includes a main body M, a pair of wing portions W, a pair of side guards G, and a pair of rear flap portions F.

The main body M extends in the longitudinal direction, and is fixed to the inner surface (surface to be mounted) of the wearer's underwear when worn. The main body M has an absorber to be described later and has a function of absorbing a liquid material (hereinafter also referred to as “liquid”) such as menstrual blood of the wearer.
The main body M has a front region M1, an intermediate region M2, and a rear region M3, which are divided along the longitudinal direction.
The front area M1 is an area arranged in front of the middle area M2 (on the abdomen side of the wearer), and is configured to face the front of the excretion area of the wearer when worn.
The intermediate area M2 is configured to face the excretion area of the wearer when worn. In the case of a napkin having a wing portion, the region in the longitudinal direction X that overlaps the entire length of the wing portion is the intermediate region M2. In the case of a napkin that does not have a wing portion, the middle region when the entire length of the napkin is divided into three is defined as an intermediate region M2. Note that the intermediate region M2 may be positioned closer to the front of the main body M as illustrated, or may be positioned at the center of the main body M in the longitudinal direction.
The rear area M3 is an area arranged behind the intermediate area M2 (back side of the wearer), and is configured to face the rear of the excretion area of the wearer when worn. In the present embodiment, the rear region M3 is formed longer in the longitudinal direction than each of the front region M1 and the intermediate region M2. Thereby, the leak of the liquid to back can be prevented effectively.

The wing portion W is configured to protrude greatly from the intermediate region M2 to the outside in the width direction.
The side guard G is disposed so as to extend in the longitudinal direction at the peripheral edge in the width direction of the main body M including the intermediate region M2. The side guard G functions as a side gather that rises toward the skin side when a thread-like elastic member is disposed in an extended state near the free end 141 of the side seat 14.

The rear flap portion F is configured to bulge outward in the width direction from the rear region M3, and can be fixed to a region facing the buttocks of the inner surface of the wearer's underwear when worn. Thereby, the back flap part F can prevent the position shift of the back area | region M3 accompanying the operation | movement of a wearer at the time of mounting | wearing, and can support the back leak prevention function by the back area | region M3.
The napkin 1 may not have at least one of the wing part W, the side guard G, and the rear flap part F.

[Configuration of each part of the napkin]
3 is a cross-sectional view taken along line III-III in FIG.
The napkin 1 includes an absorbent body 11, a top sheet 12, a back sheet 13, a pair of side sheets 14, an adhesive portion 15, and a pressing groove 16.
In addition, the main body M has the structure which has the absorber 11, the surface sheet 12, and the back surface sheet 13, and these were laminated | stacked.

The absorbent body 11 has a longitudinal direction in the X-axis direction, and is disposed at the center in the thickness direction of the napkin 1. The absorber 11 absorbs the excreted liquid from the surface on the surface sheet 12 side and diffuses the liquid inside to hold the liquid.
The absorbent body 11 has an absorbent core 20 and a core wrap sheet 30.

The absorbent core 20 has a function of absorbing and holding the liquid. The absorbent core 20 may be formed of, for example, a fiber assembly made of hydrophilic fibers such as pulp fibers, or may have a configuration in which a water absorbent polymer is held in the fiber assembly. . The detailed configuration of the absorbent core 20 will be described later.
The absorbent core 20 has a first surface 20 a that faces the top sheet 12 and a second surface 20 b that faces the back sheet 13. In the present embodiment, the first surface 20a is configured as a structural surface having a convex structure or a groove, and the second surface 20b is configured as a flat surface.

  The core wrap sheet 30 covers the absorbent core 20 and has, for example, a function of maintaining the shape of the absorbent core 20. The core wrap sheet 30 is formed of, for example, thin and soft paper such as tissue paper, liquid permeable nonwoven fabric, or the like.

  The top sheet 12 is configured as a liquid-permeable sheet material and is disposed on the absorber 11. The topsheet 12 includes an outer surface 12a that constitutes the surface of the napkin 1 (surface in the thickness direction) in the main body M.

  The back sheet 13 is disposed to face the top sheet 12 in the thickness direction with the absorber 11 interposed therebetween. The back sheet 13 includes an outer surface 13a that constitutes the back surface (the lower surface in the thickness direction) of the napkin 1, and is disposed on the entire body M, the wing portion W, and the rear flap portion F.

  The pair of side sheets 14 are opposed to each other in the width direction with the top sheet 12 interposed therebetween, and are disposed on the periphery in the width direction of the napkin 1.

  The adhesive portion 15 is a configuration for fixing the napkin 1 to the underwear, and is formed on the outer surface 13 a of the back sheet 13. The adhesive part 15 includes, for example, a main body adhesive part 151 provided in the main body M, a wing adhesive part (reference numeral 152 in FIG. 12 described later) provided in the wing part W, and a rear flap adhesive part 153 provided in the rear flap part F. And having.

The pressing groove 16 is configured as a linear groove formed by pressing the absorber 11 and the top sheet 12. The pressing groove 16 is configured to go around the main body M as shown in FIGS.
The compressed groove 16 can induce deformation into a shape that fits the wearer when worn, and can enhance the effect of preventing leakage of the napkin 1 outward in the width direction and the longitudinal direction.

[Detailed structure of absorbent core]
3 is a cross-sectional view of the rear core portion 23 of the napkin 1 shown in FIG.
FIG. 4 is a plan view showing the configuration of the absorbent core 20 that constitutes a part of the absorbent body 11. FIG. 4 is a plan view of the absorbent core 20 alone before being assembled as the napkin 1. Therefore, in the absorptive core 20 shown by FIG. 4, it is the state by which the groove | channel by the pressing groove 16 is not formed.

(Overall structure of absorbent core)
The absorptive core 20 includes a front core portion 21 and a rear core portion 23 that are positioned on both ends in the longitudinal direction, and an intermediate core portion 22 that is positioned between the front core portion 21 and the rear core portion 23. The absorbent core 20 has a planar shape constricted in the intermediate core portion 22. The front core portion 21 of the absorbent core 20 is only in the front region M1, the intermediate core portion 22 is in the range extending from the front region M1 to the rear region M3 through the intermediate region M2, and the rear core portion 23 is only in the rear region M3. Be placed.

The front core portion 21 and the rear core portion 23 are located on both end sides in the longitudinal direction. The front core part 21 and the rear core part 23 can be respectively arranged in front and rear of the excretion area of the wearer when worn.
The intermediate core part 22 is located between the front core part 21 and the rear core part 23 and is formed narrower than the front core part 21 and the rear core part 23.

  In the present embodiment, the front core portion 21 and the rear core portion 23 may each include boundary portions 21 a and 23 a that are adjacent to the intermediate core portion 22 and have a width that decreases toward the intermediate core portion 22. The boundary portions 21a and 23a may have a line-symmetric shape or an asymmetric shape with respect to an axis of symmetry parallel to the Y-axis direction. By providing the boundary portions 21a and 23a, it is possible to suppress the deformation of the boundary portions 21a and 23a with respect to the external force inward in the width direction and to effectively suppress the deformation of the intermediate core portion 22.

  The absorptive core 20 has the 1st surface 20a and the 2nd surface 20b which mutually oppose along a thickness direction.

  The first surface 20 a is a surface on the side where the top sheet 12 is disposed via the core wrap sheet 30. The outer surface 12a of the top sheet 12 is a skin contact surface. When the napkin 1 is worn by the wearer, the first surface 20a is located on the skin side of the wearer.

  The second surface 20 b is a surface on the side where the back surface sheet 13 is disposed via the core wrap sheet 30. The napkin 1 is configured to be fixable to the inner surface of the undergarment by the adhesive portion 15 formed on the outer surface 13a of the back sheet 13. When the napkin 1 is worn by the wearer, the second surface 20b is located on the inner surface side of the underwear. The second surface 20b is a substantially flat surface.

The first surface 20a has a plurality of longitudinal groove portions 27 and transverse groove portions 28 that intersect each other.
In the absorbent core 20, the longitudinal groove portion 27 and the lateral groove portion 28 are provided symmetrically about a straight line extending in the longitudinal direction (X-axis direction) passing through the center in the width direction (Y-axis direction) of the absorbent core 20. .
The plurality of lateral grooves 28 are arranged in the longitudinal direction and extend in the width direction orthogonal to the longitudinal direction.
The plurality of longitudinal groove portions 27 are arranged in the width direction and extend in the longitudinal direction.

By providing the vertical groove portion 27 and the horizontal groove portion 28, the flexibility of the absorbent core 20 can be increased, and the liquid absorption speed can be increased by drawing the liquid into the groove. Further, the absorbent core 20 is partitioned into a plurality of block portions by the vertical groove portion 27 and the horizontal groove portion 28, so that the surface area of the absorbent core 20 can be increased and the liquid can be efficiently absorbed and held.
Each of the block parts has a quadrilateral shape, a substantially fan shape, or a shape lacking a part of a rectangle when viewed from above. In any block part, the top part is a substantially flat surface.

  The first surface 20 a includes a plurality of convex block portions that are partitioned by the vertical groove portions 27 and the horizontal groove portions 28. The absorptive core 20 has a concavo-convex structure resulting from a basis weight distribution or the like on the first surface 20a. Since the basis weight has a correlation with the rigidity, the deformation of the absorbent core 20 with respect to the external force applied at the time of mounting can be controlled by adjusting the basis weight distribution.

The intermediate core portion 22 includes a high basis weight portion 24 and a pair of low basis weight portions 25. In FIG. 4, the high basis weight portion 24 is indicated by a dense dot pattern, and the low basis weight portion 25 is indicated by a coarse dot pattern.
Among the block portions arranged in the intermediate core portion 22, the high basis weight portion 24 is configured by a block portion group arranged in the center two rows. The low basis weight portion 25 is configured by a block portion group arranged in a row on each side of the high basis weight portion 24.
The high basis weight portion 24 has a higher basis weight than the low basis weight portion 25.
The high basis weight part 24 may be disposed so as to face the excretion area of the wearer when worn.

As shown in FIG. 4, the first surface 20 a includes a front structural surface 51 located on the front core portion 21, a liquid receiving surface 52 located on the intermediate core portion 22, and a rear structural surface located on the rear core portion 23. 53. The front structure surface 51 is adjacent to the liquid receiving surface 52. The rear structure surface 53 is adjacent to the liquid receiving surface 52.
The absorbent core 20 has a constricted shape in which the width D2 of the liquid receiving surface 52 is narrower than the width D1 of the front structure surface 51 and the width D3 of the rear structure surface 53.

The front structure surface 51 and the rear structure surface 53 have a shape in which a plurality of grooves are formed on flat surfaces.
On the liquid receiving surface 52, the high basis weight portion 24 has a shape that protrudes upward in the thickness direction from the low basis weight portion 25, the front core portion 21, and the rear core portion 23. Each of the high basis weight portion 24 and the low basis weight portion 25 has a shape in which a plurality of grooves are formed on a flat surface. In addition, it may replace with the form of FIG. 3, and the form in which the high basic weight part 24 protrudes below to a Z direction may be sufficient. In that case, the convex structure protruding downward through the back sheet is pushed up to the leg affixed to the undergarment, and the structure is the same as that of the embodiment of FIG.

In the absorbent core 20, the region where the groove is formed, that is, the bottom forming the groove is relatively thinner than the region of the block where the groove is not formed.
The thickness and basis weight of the absorbent core 20 are correlated. The bottom part which forms a groove part has comparatively low basic weight compared with a block part. Thereby, the rigidity of the bottom part of a groove part becomes low compared with a block part. Therefore, when an external force is applied to the absorbent core 20, the absorbent core 20 is easily deformed with the groove portion as a deformation starting point.
From the viewpoint of ease of deformation, it is desirable that each groove has a smaller basis weight of the absorbent material than the surrounding block.
Here, the “low basis weight” is a concept including not only the form in which the material of the absorbent core exists but also the form in which the material of the absorbent core does not exist. However, in the form in which the material of the absorbent core exists, the block-shaped parts of the absorbent core located on both sides of each of the grooves are connected to each other. Since it is hard to produce a cut etc. and a softness | flexibility can be provided, it is more preferable.

  In the present embodiment, each groove portion has substantially the same groove width at the bottom portion constituting the groove portion and the groove width at the opening portion of the groove portion. The bottom of the groove is positioned substantially parallel to the second surface 20b. The side surface of the groove forming the groove is substantially perpendicular to the bottom. The width of the groove described below indicates the width at the opening of the groove.

  Here, the groove portion will be described with an example in which the cross section perpendicular to the longitudinal direction of the groove portion is substantially rectangular, but the present invention is not limited to this. For example, a V-shaped or trapezoidal groove may be used as the cross section having a tapered side surface whose width increases from the bottom toward the opening. Even in such a case, in the absorbent core 20, the area where the groove is formed is lower in basis weight and the rigidity is lower than the area where the groove is not formed. For example, when the cross-sectional shape is a V-shaped or trapezoidal groove, the width of the groove indicates the width of the opening.

(Configuration of liquid receiving surface)
Next, the vertical groove portion and the horizontal groove portion arranged on the liquid receiving surface 52 corresponding to the intermediate core portion 22 will be described in detail.
The high basis weight portion 24 of the intermediate core portion 22 is formed at the center portion in the width direction of the intermediate core portion 22. The high basis weight portion 24 extends over the entire length in the longitudinal direction of the intermediate core portion 22. Here, the “center portion in the width direction” is a region located on the center side of the side portion including a center line that bisects the absorbent article in the width direction. The region including the portion facing the excretion portion of the wearer is indicated, and the rear core portion 23 indicates the region including the portion facing the fissure 61.

  The liquid receiving surface 52 includes a fourth vertical groove portion 274 as two fourth groove portions, a fifth vertical groove portion 275 as one fifth groove portion, and a plurality of horizontal groove portions 28. The fourth vertical groove portion 274 and the fifth vertical groove portion 275 are narrow vertical groove portions having the same width dimension.

The two fourth vertical groove portions 274 are spaced apart from each other and arranged in the width direction. The fourth vertical groove portion 274 has a straight portion extending in the longitudinal direction and a curved portion in which both end portions facing each other through the straight portion are curved toward the center in the width direction of the liquid receiving surface 52.
The fourth vertical groove portions 274 are arranged to face each other via the fifth vertical groove portions 275 in the width direction, and are arranged one on each side of the fifth vertical groove portions 275.

  An annular groove portion is formed by the two fourth vertical groove portions 274. A region surrounded by the annular groove corresponds to the high basis weight portion 24. The high basis weight portion 24 is composed of ten block portion groups arranged in two central rows, which are partitioned by the fourth vertical groove portion 274, the fifth vertical groove portion 275, and the horizontal groove portion 28.

  The two fourth vertical groove portions 274 can suppress the deformation of the high basis weight portion 24 due to the influence of the surrounding deformation, and can retain the shape of the intermediate core portion 22 to secure the absorption amount. be able to.

  One fifth vertical groove portion 275 is arranged at the center of the two fourth vertical groove portions 274 and extends in the longitudinal direction of the intermediate core portion 22. The fifth vertical groove portion 275 is located in the center portion of the liquid receiving surface 52 in the width direction. The fifth vertical groove portions 275 are arranged along the longitudinal direction inside the high basis weight portion 24.

(Configuration of rear structure surface)
Next, the vertical groove portion and the horizontal groove portion arranged on the rear structure surface 53 will be described in detail. The absorptive core 20 has a longitudinal groove part of two types of width dimensions. A relatively wide vertical groove portion is referred to as a thick vertical groove portion, and a narrow vertical groove portion is referred to as a thin vertical groove portion.

  With respect to the longitudinal groove portions 27 arranged on the rear structure surface 53, the thick longitudinal groove portion is referred to as a second longitudinal groove portion 272, and the narrow longitudinal groove portion is referred to as a first longitudinal groove portion 271. In addition, when it is not necessary to distinguish the 1st vertical groove part 271 and the 2nd vertical groove part 272 in particular, all are called the vertical groove part 27. FIG.

  In the present embodiment, five vertical groove portions 27 are arrayed at an equal pitch in the rear core portion 23, and among the five vertical groove portions 27, the three vertical groove portions 27 positioned at the center are formed as thick vertical groove portions ( The second longitudinal groove portion 272) and the longitudinal groove portions 27 on both left and right sides are narrow longitudinal groove portions (first longitudinal groove portions 271), thereby adjusting the rigidity distribution in the width direction of the rear core portion 23. Here, the arrangement pitch is the distance between the centers of adjacent vertical groove portions.

The rear structure surface 53 includes a first vertical groove portion 271 as two first groove portions, a second vertical groove portion 272 as three second groove portions, and a plurality of horizontal groove portions 28.
The second vertical groove portion 272 is a wider groove portion than the first vertical groove portion 271. The second groove portion 272 is provided closer to the center in the width direction than the first groove portion 271.

  As shown in FIG. 4, the rear structural surface 53 is divided into three in the width direction, a center portion 237, first side portions 238 that are both side portions located outside the center portion 237 in the width direction, and 2 side portions 239.

The three second vertical groove portions 272 are arranged in the central portion 237. Of the three second vertical groove portions 272, the middle second vertical groove portion 272 is arranged at the center in the width direction.
The two first vertical groove portions 271 are arranged one by one on each of the first side portion 238 and the second side portion 239.

  As described above, in the present embodiment, the central portion 237 has three wide second vertical groove portions 272, and the first side portion 238 and the second side portion 239 each have a narrow first vertical groove portion. Since the 271s are arranged one by one, the central portion 237 has a smaller thickness of the absorbent core 20 than the both side portions 238 and 239, and therefore the rigidity in the bending direction is lowered. Therefore, when the napkin 1 is attached and an external force is applied to the absorbent core 20, the central portion 237 is more likely to be preferentially deformed than the side portions 238 and 239 in the rear core portion 23.

  The rear structure surface 53 is composed of a total of 36 block portions, which are divided into six rows in the longitudinal direction and six columns in the width direction by the horizontal groove portion 28, the first vertical groove portion 271 and the second vertical groove portion 272. Have

  In the central portion 237 of the rear structural surface 53, two rows of block portion groups defined by the three second vertical groove portions 272 and the horizontal groove portions 28 are arranged. The dimension in the width direction of each block part of the block part groups in these two rows is shorter than the dimension in the width direction of each block part in the block part groups in the other rows. The dimensions in the width direction of the respective block portions of the block portion group located on both side portions 238 and 239 of the rear structure surface 53 are substantially the same. Here, the dimension in a block part is a dimension in the top part of the quadrilateral shape of a block part.

  In addition, the width direction dimension of each block part of the block part group located in the both sides 238 and 239 of the back structure surface 53 may not be the same. For example, as in the absorbent core 1020 shown in FIG. 14, the width dimension of the block portion located on the center side in the width direction in each of the side portions 238 and 239 is larger than the width dimension of the block portion located on the side side. It may be small.

  FIG. 14 is a partial plan view of an absorbent core 1020 as a modified example, and shows a form of grooves arranged on the rear structure surface 53 of the rear core 23. The absorbent core 1020 shown in FIG. 14 differs from the absorbent core 20 shown in FIG. 4 only in the arrangement pitch of the first vertical groove portions 271 and the second vertical groove portions 272.

Similarly to the absorbent core 20, the absorbent core 1020 is smaller in size than the other block portions in each block portion of the two rows of block portion groups arranged in the central portion 237 in the width direction. That is, the block part located in the center part 237 in the width direction is smaller than the block parts located in the side parts 238 and 239.
Each block portion of the two rows of block portion groups arranged in the center portion 237 in the width direction is formed by two second groove portions 272 and lateral groove portions 28 adjacent to each other.

  In the absorbent core 1020, two rows of block portion groups are arranged on both sides via two central rows of block portion groups. The two rows of block portion groups are located on both side portions 238 and 239, respectively. In the two rows of block portion groups respectively located on the both side portions 238 and 239, each block portion of the one row block portion group located near the center portion in the width direction is 1 located near the side edge in the width direction. It is smaller than each block portion of the block portion group of the row.

  Each block portion of the two rows of block portion groups arranged on the both side portions 238 and 239 is formed by at least the first vertical groove portion 271 and the horizontal groove portion 28. Specifically, each block portion of the row of block portions located near the side end in the width direction is formed by the side end portion of the rear structure surface 53, the first vertical groove portion 271, and the horizontal groove portion 28. Each block portion of the block portion group in one row located near the central portion in the width direction is formed by the first vertical groove portion 271 and the second vertical groove portion 272 that are adjacent to each other, and the horizontal groove portion 28.

  In the absorbent core 1020 shown in FIG. 14, the block portion gradually increases from the center in the width direction of the rear core portion 23 toward the side end.

The lateral groove portions 28 are arranged at equal intervals on the rear structure surface 53 so that the dimensions of the sides extending in the longitudinal direction of the respective block portions of the rear structure surface 53 are the same.
The widths of the plurality of lateral grooves 28 arranged on the rear structure surface 53 are all the same.
Among the plurality of lateral grooves 28 arranged on the first surface 20a of the absorbent core 20, the lateral groove 282 arranged at the boundary between the front structure surface 51 and the liquid receiving surface 52, the liquid receiving surface 52, and the rear structure. The lateral groove portion 283 as the third groove portion arranged at the boundary with the surface 53 is wider than the other lateral groove portions 28 and narrower than the second longitudinal groove portion 272 which is a thick longitudinal groove portion.
Here, reference numeral 282 is assigned to the lateral groove portion arranged at the boundary between the front structure surface 51 and the liquid receiving surface 52, and reference numeral 283 is assigned to the horizontal groove portion arranged at the boundary between the liquid reception surface 52 and the rear structural surface 53. However, when it is not necessary to distinguish from the other lateral groove portions 28, they are simply referred to as the lateral groove portions 28.

  The first vertical groove portion 271 is located on the extension lines 43 and 44 of the side edge portions 41 and 42 that define the width D2 of the liquid receiving surface 52, or on the inner side of the extension line.

The above-described absorbent core 20 is typically a mixed fiber obtained by mixing and mixing pulp fibers and an absorbent polymer.
Examples of hydrophilic fibers contained in the absorbent core 20 include cellulose-based hydrophilic fibers such as pulp fibers, rayon fibers, cotton fibers, and cellulose acetate, polyolefin-based fibers such as polyethylene and polypropylene, and condensations such as polyester and polyamide. 1 type (s) or 2 or more types chosen from system fiber etc. can be used.
Examples of the water-absorbing polymer contained in the absorbent core 20 include sodium polyacrylate, acrylic acid-vinyl alcohol copolymer, cross-linked sodium polyacrylate, starch-acrylic acid graft copolymer, and isobutylene-maleic anhydride. 1 type (s) or 2 or more types chosen from a copolymer, its saponification thing, poly aspartic acid, etc. can be used.

  The absorptive core 20 having a concavo-convex structure on the rear structure surface 53 can be manufactured using, for example, a stacking apparatus including a stacking drum having a concave portion for accumulation on the outer peripheral surface. In the fiber stacking apparatus, the core material is deposited in the accumulation recess by supplying the core material such as pulp fiber to the outer peripheral surface of the fiber stacking drum. An absorptive core can be obtained by releasing the accumulated fiber body from the concave portion for accumulation.

[Operational effects of this embodiment]
FIG. 5 is a schematic diagram for explaining the relationship between the tear 61 of the wearer's buttocks 60 and the deformation state of the rear region M3 of the napkin 1 when the napkin 1 of the present embodiment is worn.

  The rear core portion 23 of the absorbent core 20 has a rear structure surface 53 including a plurality of first vertical groove portions 271 and a plurality of second vertical groove portions 272 wider than the first vertical groove portions 271. The second vertical groove portion 272 is arranged in the center portion 237 in the width direction of the rear core portion 23.

  Thereby, the central portion 237 where the second vertical groove portions 272 are arranged has lower rigidity in the bending direction than the portion where the first vertical groove portions 271 are arranged. Therefore, when the napkin 1 is worn by the wearer, the central portion 237 where the wide second vertical groove portions 272 are arranged in the rear core portion 23 is narrow with the second vertical groove portion 272 as a deformation starting point. The first vertical groove portion 271 is easily deformed so as to protrude to the first surface 20a preferentially over the portion where the first vertical groove portion 271 is arranged. And as shown in FIG. 5, since the center part 237 of the back core part 23 deform | transforms so that it may protrude to the skin side along the crack 61, the clearance gap between a wearer's crack and an absorbent article Becomes smaller. Therefore, even if liquid substances such as menstrual blood excreted from the excretion area of the wearer flow out to the rear part, they are quickly absorbed by the absorbent core 20 and liquid leakage at the rear part is suppressed.

  Furthermore, since the narrow first vertical groove portions 271 are arranged on both side portions of the rear core portion 23, the first side portion 238 and the second side portion 239 are preferentially deformed. It follows the central portion 237 and easily deforms along the bulge of the buttocks. Thereby, the clearance gap between a collar part and an absorbent article becomes small, fitting property improves, and the leak of a rear part, especially a side leak are suppressed.

  Further, since the first side portion 238 and the second side portion 239 have higher bending rigidity and are less likely to be deformed than the center portion 237, the center portion 237 of the absorbent core 20 is cracked. Even if it deforms along 61, it is suppressed that the 1st side part 238 and the 2nd side part 239 deform | transform in conjunction with the deformation | transformation of the center part 237. Thereby, the twist in the back core part 23 of the absorptive core 20 at the time of mounting | wearing of the napkin 1 is suppressed.

  Moreover, since the center part 237 deform | transforms preferentially rather than the 1st side part 238 and the 2nd side part 239, when the napkin 1 is mounted | worn, a side part deform | transforms first and the napkin 1 Can be suppressed.

  Thus, the napkin 1 of this embodiment is easy to deform | transform along the shape of the collar part including the crack in the back area | region, and also can suppress a twist. Thereby, even if a liquid material such as menstrual blood of the wearer flows out to the rear core portion 23 of the napkin 1, it is quickly absorbed by the absorbent body 11 deformed along the crack 61 and leakage can be suppressed. Furthermore, liquid leakage due to the napkin 1 being swung is suppressed. In particular, when the napkin is worn on the back by the wearer at bedtime, the liquid material tends to flow backward on the back side. Therefore, the napkin 1 of the present embodiment is effective for suppressing the liquid leakage at the rear at night. is there.

  In the present embodiment, since a plurality of wide second vertical groove portions 272 are arranged in the central portion 237 in the width direction of the rear core portion 23, there are a plurality of deformation starting points in the rear core portion 23. Thereby, the area | region where a deformation | transformation in the back core part 23 becomes comparatively large can be made wide in the width direction.

  Therefore, for example, even when the napkin 1 is mounted with a deviation in the width direction, one of the plurality of second longitudinal groove portions 272 becomes a deformation starting point, and the central portion 237 of the rear core portion 23 is along the crack 61. It is transformed into a shape. Thereby, it is hard to produce a clearance gap between the napkin 1 and skin, and a liquid leak is suppressed.

  Moreover, in this embodiment, since the horizontal groove part 28 is arrange | positioned in addition to the vertical groove part 27, in the longitudinal direction of the napkin 1, it is easy to deform | transform along the shape of a mounting | wearing object site | part of a wearer, and fit property improves.

  In the present embodiment, as shown in FIG. 4, in the rear core portion 23, the first vertical groove portion 271 is opposed to both side edge portions 41 and 42 that define the width D <b> 2 that is the minimum width of the intermediate core portion 22. It is located inside the respective extension lines 43 and 44 or on the extension lines 43 and 44.

  In this way, the thick vertical groove portion is provided by providing the first vertical groove portion 271 which is not the thick vertical groove portion but the thin vertical groove portion on the extension lines 43 and 44 or inside the extension lines 43 and 44. Compared to the case, the rear flap portion F is less likely to be folded when the napkin is attached.

  That is, when the napkin is attached, the central portion 237 where the second vertical groove portion 272 that is the thick vertical groove portion of the rear core portion 23 is disposed is on the extension lines 43 and 43 or on the inner side of the extension line. 1 is easy to be deformed preferentially than the portion where the vertical groove portion 271 is arranged, and it is difficult to bend inward in the width direction outside the extension line 43, so that the rear flap portion F is folded into the topsheet 12 side. Is prevented from being deformed.

Further, in the present embodiment, a lateral groove portion 283 as a third groove portion is arranged between the intermediate core portion 22 and the rear core portion 23.
By providing the lateral groove portion 283, the napkin 1 is mounted, and when the central portion 237 of the rear core portion 23 of the absorbent core 20 is deformed along the crack starting from the second vertical groove portion 272, the rear core portion The deformation of the high basis weight portion 24 in conjunction with the deformation at 23 is suppressed. Therefore, liquid leakage due to deformation of the high basis weight portion 24 can be suppressed.

[Additional description of this embodiment]
Hereinafter, the description of this embodiment will be supplemented.

(Measuring method of groove width)
The width of the groove is determined by measuring the width at the opening of the groove. An absorptive core is placed horizontally, and the opening width is measured by adjusting the measurement magnification with a microscope (VHX-1000 manufactured by KEYENCE Corporation) to enlarge the first surface 20a.
Alternatively, the absorbent core 20 is cut using a feather blade razor, and the cross section of the cut sample is observed at a magnification of 20 to 100 times using a microscope (VHX-1000 manufactured by KEYENCE). The groove width may be measured.

(Measurement method of basis weight of each part of absorbent core)
Each part of the absorbent core 20 to be measured is cut using a single blade razor manufactured by Feather, and small pieces are obtained so as to have a predetermined area. The weights of these pieces are measured using an electronic balance (Electronic balance GR-300 manufactured by A & D, accuracy: 4 digits after the decimal point). The basis weight of the small piece is calculated by dividing the obtained weight by the area of the small piece of each part. About each of each part, let the average of the basic weight of five small pieces be a basic weight.

(Measurement method of thickness of each part of absorbent core)
The measurement of the thickness of the absorptive core which is a measuring object is performed by measuring the thickness of a small piece cut out in order to measure the basis weight of each part. A small piece cut out from the absorbent core is pressurized at a pressure of 5 kPa for 10 minutes, and measurement is performed immediately after dewetting. An acrylic plate with a size of 20 mm x 20 mm and a thickness of 3 mm is placed in the central area of the sample after dewetting, and a sample is used using a non-contact type laser displacement meter (laser head LK-G30, displacement meter LK-GD500) manufactured by KEYENCE. Measure the thickness. When the size of the cut-out piece is small and difficult to measure with a non-contact type laser displacement meter, the cross section of the cut sample is, for example, 20 to 100 using a microscope (VHX-1000 manufactured by KEYENCE). You may observe and measure at double magnification.

(Numerical examples of each component)
A numerical example of the absorbent core will be described. In addition, it is not limited to the numerical value described here. The widths of the thick vertical groove portion and the narrow vertical groove portion can be appropriately set according to the width of the absorbent core, the depth of the groove portion, the bottom of the groove portion, and the thickness of the block portion. The thickness of the bottom of the groove and the block is correlated with the basis weight. The thickness and basis weight of the bottom part of the groove part and the block part are appropriately set so that a sufficient absorption amount can be obtained while providing a comfortable wearing feeling with an appropriate thickness that does not give the wearer an uncomfortable feeling.

  The width a of the first vertical groove portion 271 which is a narrow vertical groove portion is preferably 0.5 mm or more and 2.5 mm or less, more preferably 1 mm or more and 2 mm, in order to make the rear portion soft and easy to deform along the collar portion. It is as follows. In the present embodiment, the width a of the first vertical groove portion 271 is 1.5 mm.

  The width b of the second vertical groove portion 272, which is a thick vertical groove portion, is preferably 2.5 mm or more and 5.5 mm or less in order for the center portion to be easily bent along the collar portion and to have sufficient strength. More preferably, it is 3 mm or more and 5 mm or less. In the present embodiment, for example, the width of the second vertical groove b is 4 mm.

  The difference between the width “a” of the first vertical groove portion 271 that is the fine vertical groove portion and the width “b” of the second vertical groove portion 272 that is the thick vertical groove portion is preferably 1 from the viewpoint of further facilitating the above-described effect. It is 0.5 mm or more and 3.5 mm or less, More preferably, it is 2 mm or more and 3 mm or less.

  The width c of the lateral groove portion 283 arranged at the boundary between the intermediate core portion 22 and the rear core portion 23, in other words, extending in the Y-axis direction between the high basis weight portion 24 and the rear core portion 23. Is 1.5 mm or more and 3.5 mm or less, more preferably 2.0 mm or more and 3.0 mm or less. In the present embodiment, the width c of the lateral groove portion 283 is 2.5 mm.

The width D3 of the rear core portion 23 is preferably 60 mm or more and 100 mm or less, more preferably 70 mm or more and 90 mm or less, and in this embodiment, it is 80 mm.
The arrangement pitch of the longitudinal groove portions 27 arranged in the rear core portion 23 is, for example, 11 mm or more and 15 mm or less, and is 13 mm in this embodiment.

  The groove depth d1 of the first vertical groove portion 271, the second vertical groove portion 272, and the horizontal groove portion 28 is 1.5 mm or more and 6.0 mm or less, and is 4 mm in this embodiment. The groove depth refers to the distance from the opening to the bottom of the groove located on the same plane as the top of the block.

The thickness of the bottom part of the horizontal groove part 28 and the vertical groove part 27 is 0.5 mm or more and 6.0 mm or less, for example. The basis weight of the bottom surface of the horizontal groove portion 28 and the vertical groove portion 27 is, for example, 25 g / m ² or more and 300 g / m ² or less.
The thickness of the block part of the back core part 23 is 2 mm or more and 10 mm or less, for example. The basis weight of the block portion of the rear core part 23 is, for example, 100 g / ^{m 2} or more 500 g / ^{m 2} or less.

  The width e of the fourth vertical groove portion 274 and the width g of the fifth vertical groove portion 275 in the intermediate core portion are preferably 0.5 mm or more and 10 mm or less, and more preferably 1 mm or more and 5 mm or less. In the present embodiment, the width of the fourth vertical groove portion 274 and the fifth vertical groove portion 275 is 1.5 mm.

The groove depths of the fourth vertical groove portion 274 and the fifth vertical groove portion 275 are preferably 0.5 mm or more and 10 mm or less, more preferably 3 mm or more and 5 mm or less, for example, 4 mm. The groove depth of the fourth vertical groove portion 274 is a distance from the opening portion to the bottom portion of the fourth vertical groove portion 274 located on the same plane as the top portion of the block portion of the low basis weight portion 25.
Similarly, the groove depth of the lateral groove portion 28 arranged inside the low basis weight portion 25 is preferably 0.5 mm or more and 10 mm or less, more preferably 3 mm or more and 5 mm or less, for example, 4 mm.

The thickness of the low basis weight part 25 is 2 mm or more and 12 mm or less, for example, Preferably, it is 3 mm or more and 10 mm or less. The basis weight of the bottom surface of the low basis weight portion 25 is, for example, 100 g / m ² or more and 700 g / m ² or less, and preferably 200 g / m ² or more and 600 g / m ² or less.
The thickness of the high basis weight part 24 is 3 mm or more and 15 mm or less, for example, Preferably they are 5 mm or more and 13 mm or less. The basis weight of the bottom surface of the low basis weight portion 25 is, for example, 400 g / m ² or more and 1000 g / m ² or less, and preferably 500 g / m ² or more and 900 g / m ² or less.
The difference between the thickness of the block portion in the high basis weight portion 24 and the thickness of the block portion in the low basis weight portion 25 is preferably 1 mm or more and 3 mm or less, and for example, 2 mm in this embodiment.

<Other embodiments>
The form of the groove part arranged on the rear structure surface of the rear core part is not limited to the first embodiment.
Hereinafter, as other embodiments, the second to eighth embodiments will be described as examples.

Each of the absorbent cores shown in the following embodiments has a first surface and a second surface facing each other along the thickness direction, similar to the absorbent core 20 of the first embodiment. When the absorbent core is incorporated into the napkin, the first surface on the side where the topsheet is disposed has a groove.
The plan view of the absorbent core used in the description of each embodiment corresponds to the plan view on the first surface side where the grooves are arranged.

  As for the absorptive core shown to each embodiment, all are the absorptive core 20 of 1st Embodiment, the point by which a thick vertical groove part and a thin vertical groove part are arranged in a back core part, the center part of the width direction of a back core part This is common in that the thick vertical groove portions are arranged in line and the groove portions are arranged in line symmetry.

  When a napkin incorporating such an absorbent core is mounted, the thick vertical groove portion becomes a deformation starting point, and the central portion of the rear core portion is deformed preferentially over other portions, and the first surface side It becomes a structure which is easy to deform so as to protrude.

  Accordingly, as shown in FIG. 5, the central portion 237 of the rear core portion 23 is deformed so as to protrude toward the skin with the thick vertical groove portion as a deformation starting point, and the napkin is easily deformed along the crack 61. Thereby, the clearance gap between the crack 61 and a napkin can be made small, and the liquid leak in the back of a napkin is suppressed.

  Further, in each of the following embodiments, since the narrow vertical groove portions are arranged on both side portions of the rear core portion 23, the both side portions follow the central portion deformed preferentially than the both side portions, and the flange portion Deforms along the bulge. Thereby, the clearance gap between a collar part and an absorbent article becomes small, and the leak of a rear part, especially a side leak are suppressed.

  Hereinafter, in each embodiment, a different structure from 1st Embodiment is mainly demonstrated, the same code | symbol is attached | subjected about the same structure, and the description is abbreviate | omitted.

<Second Embodiment>
FIG. 6 is a partially enlarged plan view of the rear core portion 23 of the absorbent core 120 according to the second embodiment.
As shown in FIG. 6, it is good also as the absorptive core 120 by which the 2nd vertical groove part 272 which is a thick vertical groove part is arranged in the center of the width direction Y of the back core part 23. As shown in FIG. The second vertical groove portion 272 is arranged so as to cut the entire length of the absorbent core 120 through the front core portion 21, the intermediate core portion 22, and the rear core portion 23 without changing the width along the longitudinal direction. May be.
Two first vertical groove portions 271 that are narrow vertical groove portions are arranged in each of both sides in the width direction via the second vertical groove portion 272. The number of narrow grooves is not limited to these. Further, the second vertical groove portion 272 is allowed to slightly shift from the center in the width direction to the side direction.

<Third Embodiment>
As shown in FIG. 7, the absorbent core 220 may have different widths of the second vertical groove portions 272 that are three thick vertical groove portions arranged in the center portion in the width direction of the rear core portion 23. Of the two second vertical groove portions arranged in the center in the width direction, the second vertical groove portion 272 in the middle is wider than the second vertical groove portions 272 that are respectively located on both sides thereof. The second vertical groove portions 272 on both sides have the same width.

  The first vertical groove portions 271 that are a pair of narrow vertical groove portions are arranged to face each other via the second vertical groove portions 272 in the width direction. The second vertical groove portion 272 is wider than the first vertical groove portion 271.

  As described above, when a plurality of thick vertical groove portions are provided in the central portion of the rear core portion 23 in the width direction, the widths of the thick vertical groove portions may be different from each other. In the case where a plurality of thick vertical groove portions having different widths are provided, it is further desirable that the widest wide vertical groove portion among these thick vertical groove portions is arranged at the center of the rear core portion 23. As a result, the widest wide vertical groove portion tends to be a deformation starting point.

  In addition, the rear core portion 23 of the absorbent core 220 has the lowest rigidity at the central portion in the Y-axis direction by varying the width of the thick longitudinal groove portion, and is gradually increased from the central portion toward the side edge portion. Becomes higher. As described above, by changing the degree of deformation in the rear core portion 23 in the Y-axis direction, the fit to the heel portion is improved. Thereby, the clearance gap between a collar part and a napkin can be made small, and a leak, especially a side leak are suppressed.

<Fourth Embodiment>
As shown in FIG. 8, it is good also as the absorptive core 320 which does not provide a horizontal groove part but has only a vertical groove part. In the rear core portion 23 of the absorbent core 320, three second vertical groove portions 272 extending in the longitudinal direction, which are thick vertical groove portions, are arranged in the center portion in the width direction. The first vertical groove portions 271 that are narrow vertical groove portions are arranged on both sides via the three second vertical groove portions 272.

<Fifth Embodiment>
As shown in FIG. 9, it is good also as the absorptive core 420 by which the 2nd vertical groove part 272 which is two thick vertical groove parts is arranged in the center part of the width direction of the back core part 23. As shown in FIG. The second vertical groove portion 272 is arranged so that the middle of the two second vertical groove portions 272 is located at the center in the width direction of the rear core portion 23. The first vertical groove portions 271 that are narrow vertical groove portions are arranged on both sides so as to sandwich the two second vertical groove portions 272.

<Sixth Embodiment>
As shown in FIG. 10, as the absorbent core 520 in which the second vertical groove portions 272 that are a plurality of thick vertical groove portions having a length less than the total length in the longitudinal direction of the rear core portion 23 are arranged in the rear core portion 23. Also good. The first vertical groove portions 271 are arranged on both sides so as to sandwich the three second vertical groove portions 272. In this way, the thick vertical groove portions arranged in the rear core portion 23 do not cut the entire length in the longitudinal direction of the rear core portion 23, and the length may not reach the intermediate core portion 22. It does not have to reach the rear end of the core 520.

<Seventh Embodiment>
FIG. 11 is a plan view of the absorbent core 620 of the present embodiment.
FIG. 2 is a plan view of the napkin 601 in which the absorbent core 620 is incorporated.
12 is a cross-sectional view of the intermediate core portion 22 of the napkin 601 in which the absorbent core 620 is incorporated, and is a cross-sectional view taken along the line XII-XII of the napkin 601 shown in FIG.

In the absorbent core 20 of the first embodiment, the fourth vertical groove portion 274 and the fifth vertical groove portion 275 have the same width dimension and are arranged in the high basis weight portion 24. 275 was a narrow narrow vertical groove.
On the other hand, in the absorbent core 620 of the present embodiment, the fifth vertical groove portions 275 arranged inside the high basis weight portion 24 are wide thick vertical groove portions. The fifth vertical groove portion 275 is wider than the fourth vertical groove portion 274 provided around the high basis weight portion 24. In addition, the structure in the back core part 23 of the absorptive core 620 is the same as that of the back core part 23 of the absorptive core 20 of 1st Embodiment.

As described above, in the present embodiment, the fifth vertical groove portion 275 wider than the fourth vertical groove portion 274 provided around the high basic weight portion 24 is arranged inside the high basic weight portion 24. Yes.
Thereby, even if the napkin is mounted from behind by the wearer, and the intermediate core portion 22 is positioned corresponding to the wearer's crack, the high basis weight portion 24 is formed with the fifth longitudinal groove portion 275 as the deformation starting point. Deforms so that it protrudes preferentially toward the skin. Therefore, the napkin is deformed so as to follow the crack, the gap between the crack and the napkin can be reduced, and the backward liquid leakage can be suppressed.

The width e of the fourth vertical groove portion, which is a narrow vertical groove portion in the present embodiment, is the same as the width e of the fourth vertical groove portion described in the first embodiment.
The width g of the fifth vertical groove portion 275 is preferably 1 mm or more and 10 mm or less, and more preferably 1 mm or more and 5 mm or less. In the present embodiment, the width g of the fifth vertical groove portion 275 is 3 mm. The width g of the fifth vertical groove portion 275 is preferably 0.5 mm or more and 5 mm or less, and more preferably 1 mm or more and 3 mm or less, than the width e of the fourth vertical groove portion 274.

As shown in FIG. 12, the groove depth d2 in the fifth vertical groove portion 275 is preferably 0.5 mm or more and 10 mm or less, more preferably 4 mm or more and 7 mm or less, for example 6 mm. The groove depth of the fifth vertical groove portion 275 is a distance from the opening portion to the bottom portion of the fifth vertical groove portion 275 located on the same plane as the top portion of the high basis weight portion 24.
On the other hand, the groove depth d3 of the fourth vertical groove portion 274 is the same as the groove depth of the fourth vertical groove portion 274 described in the first embodiment, and is 4 mm, for example.
Similarly, the groove depth of the lateral groove portion 28 arranged inside the high basis weight portion 24 is preferably 4 mm or more and 7 mm or less, for example, 6 mm.

<Eighth Embodiment>
FIG. 13 is a plan view of the absorbent core 720 in this embodiment.

  In the absorbent core 20 of the first embodiment, on the extension lines 43 and 44 that extend the opposite side edge portions 41 and 42 that respectively define the width D2 that is the minimum width of the intermediate core portion 22 to the rear core portion 23, Or the 1st vertical groove part 271 was arranged inside the extension line.

  On the other hand, in the present embodiment, the first longitudinal axis is formed outside the extension lines 43 and 44 of the side edge portions 41 and 42 that define the width D2 of the rear core portion 23 that is the minimum width of the intermediate core portion 22. The groove portions 271 are arranged. No groove is arranged on the extension lines 43 and 44.

  Thus, by providing the first vertical groove portion 271 that is a narrow vertical groove portion in the region outside the region sandwiched between the extension lines 43 and 44, compared to the case where the thick vertical groove portion is provided, when mounting the napkin, The rear flap part F is not easily folded.

  That is, when the napkin is attached, the central portion in the width direction in which the second vertical groove portions 272 of the rear core portion 23 of the absorbent core 20 are arranged is located in a region outside the region sandwiched between the extension lines 43 and 44. Since it deform | transforms preferentially rather than the part in which the 1st vertical groove part 271 is arranged, it is suppressed that the back flap part F deform | transforms so that it may be folded in to the surface sheet 12 side.

  The embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the embodiment of the present invention can be an embodiment in which the embodiments are combined.

  For example, although the absorptive core of each above-mentioned embodiment had the plane shape which has a constriction in the middle core part, it is good also as an absorptive core of the plane shape without a constriction.

  As yet another embodiment, a pair of lateral sides facing each other along the width direction are arranged in the width direction by mixing a narrow vertical groove portion and a thick vertical groove portion at the center portion in the width direction of the rear core portion. It is good also as an absorptive core by which a narrow vertical groove part is arranged in each part.

Specifically, for example, three thick vertical groove portions and two narrow vertical groove portions extending in the longitudinal direction along the width direction are arranged in the central portion of the rear core portion. In the central portion, one thick vertical groove portion is arranged at the center in the width direction, and one thin vertical groove portion is arranged on each side of the thick vertical groove portion, and the one thick vertical groove portion and the two thin vertical groove portions are interposed therebetween. Thus, one thick vertical groove is arranged on each side.
Since the absorbent core having such a configuration is provided with a thick vertical groove at the center, the center is less rigid than the side. Therefore, the center part of an absorptive core becomes easy to change along a crack when it is equipped.

Moreover, the liquid receiving surface of the absorptive core of each above-mentioned embodiment has a high basic weight part and a low basic weight part. On the other hand, as another embodiment, the liquid receiving surface may be configured to have a uniform basis weight within the surface.
Moreover, in the above-mentioned embodiment, although the basic weight of the block part of the low basic weight part of a liquid-receiving surface was made the same as the basic weight of the block part of a front structure surface and a back structure surface, as other embodiment, , May be different.

  Moreover, in the back core part of the absorptive core of each above-mentioned embodiment, although the case where the basis weights of the block part and the bottom part of the groove part are different was described as an example, it is not limited thereto, for example, the block part and The basis weight of the bottom of the groove may be equal. It is sufficient that at least the thickness of the bottom of the groove is thinner than the thickness of the block, so that the region where the groove is arranged is more easily deformed than the region where the block is located.

  Moreover, in the above-mentioned embodiment, although the example which manufactures the absorptive core which has an uneven | corrugated structure in a back structure surface using the fiber stacking apparatus was given, it is not limited to this. For example, an absorbent core having a concavo-convex structure may be manufactured by partially pressing one surface of an absorbent core having a substantially flat surface with a substantially uniform in-plane thickness to form a groove.

  Moreover, in each above embodiment, although the example of the sanitary napkin was shown as an absorbent article, it is not limited to this. The absorbent article of the present invention may be, for example, an incontinence pad, a cage sheet, a disposable diaper, or the like.

  This invention discloses the following absorbent articles further regarding embodiment mentioned above.

<1> An absorptive core having a front core portion and a rear core portion located on both ends in the longitudinal direction is provided, and the rear core portion is arranged in a width direction orthogonal to the longitudinal direction and extends in the longitudinal direction. A plurality of first groove portions and a single or a plurality of second groove portions that are provided closer to the center in the width direction than the first groove portions, extend in the longitudinal direction, and are wider than the plurality of first groove portions. And an absorbent article having a structural surface.
<2> The absorbent article according to <1>, wherein at least three of the second groove portions are arranged in a central portion in the width direction, and the first groove portions are in the width direction of the central portion. An absorptive article arranged at least one by one on both sides located outside.
<3> The absorbent article according to <1> or <2>, wherein the absorbent core further includes an intermediate core portion located between a front core portion and a rear core portion, and the intermediate core The portion has a liquid receiving surface adjacent to the structural surface, and the liquid receiving surface is provided around a high basis weight portion provided at a center portion in the width direction and the high basis weight portion. The absorbent article which has a low basic weight part whose basic weight is lower than a basic weight part.
<4> The absorbent article according to <3>, wherein the absorbent core is provided along the width direction between the structural surface and the liquid receiving surface, and more than the second groove portion. An absorbent article further comprising a narrow third groove.
<5> The absorbent article according to <3> or <4>, wherein the intermediate core portion includes a fourth groove portion provided around the high basis weight portion, and the high basis weight portion. An absorbent article further comprising a fifth groove portion provided along the longitudinal direction inside and wider than the fourth groove portion.
<6> The absorbent article according to <5>, wherein a width of the fifth vertical groove portion is 0.5 mm or more and 5 mm or less larger than a width of the fourth vertical groove portion, preferably 1 mm or more and 3 mm. The following is a large, absorbent article.
<7> The absorbent article according to <5> or <6>, wherein a groove depth in the fifth vertical groove portion is 0.5 mm or more and 10 mm or less, preferably 4 mm or more and 7 mm or less. , Absorbent articles.
<8> The absorbent article according to any one of <3> to <7>, wherein the intermediate core part is formed narrower than the front core part and the rear core part, 1st groove part is an absorbent article provided in the extension line in the said back core part of the both-sides edge part which prescribes | regulates the minimum width | variety of the said intermediate core part, or an inner side rather than the said extension line in the said back core part, respectively.
<9> The absorbent article according to any one of <1> to <8>, wherein the absorbent core is arranged in a longitudinal direction and extends in a width direction perpendicular to the longitudinal direction. An absorbent article having:
<10> The absorbent article according to any one of <1> to <9>, wherein the structural surface is formed by the horizontal groove portion, the first vertical groove portion, and the second vertical groove portion. An absorbent article having a block part.
<11> The absorbent article according to <10>, wherein in the structural surface, the block portion located in the center portion in the width direction is smaller than the block portion located in the side portion in the width direction. Goods.
<12> The absorbent article according to <10> or <11>, wherein at least the block portion formed of the first groove portion and the lateral groove portion is a lateral portion with respect to the width direction rather than the central portion. Absorbent article that is bigger.
<13> The absorbent article according to any one of <10> to <12>, wherein the block portion has a thickness of 2 mm or greater and 10.0 mm or less.
<14> The absorbent article according to any one of <10> to <13>, wherein the basis weight of the block portion is 100 g / m ² or more and 500 g / m ² or less. .
<15> The absorbent article according to any one of <9> to <14>, wherein in the structural surface, the lateral groove portions are arranged at equal intervals along a longitudinal direction. Goods.
<16> The absorbent article according to any one of <1> to <15>, wherein the width of the first vertical groove is not less than 0.5 mm and not more than 2.5 mm, preferably not less than 1 mm. An absorbent article that is 2 mm or less.
<17> The absorbent article according to any one of <1> to <16>, wherein the width of the second vertical groove is 2.5 mm or more and 5.5 mm or less, preferably 3 mm. The absorbent article which is 5 mm or less.
<18> The absorbent article according to any one of <1> to <17>, wherein a difference between a width of the first vertical groove portion and a width of the second vertical groove portion is 1 An absorbent article having a thickness of 5 mm to 3.5 mm, more preferably 2 mm to 3 mm.
<19> The absorbent article according to any one of <1> to <18>, wherein the transverse groove is arranged at a boundary between the intermediate core part and the rear core part.
<20> The absorbent article according to <19>, wherein the width of the lateral groove provided in the boundary is 1.5 mm or more and 3.5 mm or less, preferably 2.0 mm or more and 3.0 mm or less. , Absorbent articles.
<21> The absorbent article according to any one of <1> to <20>, wherein the width of the rear core portion is 60 mm or greater and 100 mm or less.
<22> The absorbent article according to any one of <1> to <21>, in which an arrangement pitch of the longitudinal groove portions arranged in the rear core portion is 11.0 mm or more and 15.0 mm or less. There is an absorbent article.
<23> The absorbent article according to any one of <1> to <22>, wherein a groove depth of the first vertical groove portion and the second vertical groove portion is 1.5 mm or more 6. Absorbent article which is 0.0 mm or less.
<24> The absorbent article according to any one of <1> to <23>, wherein a thickness of a bottom portion of the first vertical groove portion and the second groove portion is 0.5 mm or more and 6.0 mm. Absorbent articles that are:
<25> The absorbent article according to any one of <1> to <24>, wherein a basis weight of a bottom surface of the first vertical groove portion and the second vertical groove portion is 25 g / m ² or more. An absorptive article which is 300 g / m ² or less.
<26> The absorbent article according to any one of <1> to <25>, which is a sanitary napkin.

1 ... Napkins (Sanitary napkins, absorbent articles)
20, 120, 220, 320, 420, 520, 620, 720, 1020, 2020 ... absorbent core 21 ... front core portion 22 ... intermediate core portion 23 ... rear core portion 24 ... high basis weight portion 25 ... low basis weight portion 41, 42 ... side edge portions 43, 44 ... extension line 52 ... liquid receiving surface 53 ... rear structural surface (structural surface)
237 ... central part 238 ... first side part (side part)
239 ... 2nd side part (side part)
271: First vertical groove (first groove)
272: Second vertical groove (second groove)
274 ... Fourth vertical groove (fourth groove)
275: Fifth vertical groove (fifth groove)
283 ... Lateral groove (third groove)

Claims (5)

Comprising an absorbent core having a front core portion and a rear core portion located on both ends in the longitudinal direction;
The rear core portion is
A plurality of first grooves arranged in a width direction orthogonal to the longitudinal direction and extending in the longitudinal direction;
A structural surface provided on the center side in the width direction with respect to the first groove portion, extending in the longitudinal direction, and including a single groove or a plurality of second groove portions wider than the plurality of first groove portions; And
At least three of the second groove portions are arranged in the central portion in the width direction,
The said 1st groove part is an absorptive article arranged at least 1 each in the both-sides part located in the width direction outer side of the said center part . The absorbent article according to claim 1 ,
The absorbent core further includes an intermediate core portion located between the front core portion and the rear core portion,
The intermediate core portion has a liquid receiving surface adjacent to the structural surface,
The liquid receiving surface includes a high basis weight portion provided at a center portion in the width direction and a low basis weight portion provided around the high basis weight portion and having a basis weight lower than that of the high basis weight portion. Absorbent article. The absorbent article according to claim 2 ,
The absorbent core further includes a third groove portion that is provided along the width direction between the structural surface and the liquid receiving surface and is narrower than the second groove portion. The absorbent article according to claim 2 or claim 3 ,
The intermediate core part is
A fourth groove provided around the high basis weight portion;
An absorbent article further comprising a fifth groove portion provided along the longitudinal direction inside the high basis weight portion and wider than the fourth groove portion. The absorbent article according to any one of claims 2 to 4 ,
The intermediate core part is formed narrower than the front core part and the rear core part,
The plurality of first groove portions are respectively provided on an extension line in the rear core portion of both side edges that define a minimum width of the intermediate core portion or on an inner side of the extension line in the rear core portion. Goods.

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